This 17 inch replacement pad holder is used on the . This pad driver can be swapped out with the standard brush that comes standard with your purchase of the Viper AS430C scrubber. The teeth on the underside of the pad holder keep the pad attached with the help of the center locking nut that threads tightly into the middle of the driver. Use with the correct type of to customize your scrubber for nearly any flooring surface. Pair the pad and driver with the right and you're set to scrub.